A U.S. Army brigade will begin sending small teams into as many as 35 African nations early next year, part of an intensifying Pentagon effort to train countries to battle extremists and give the U.S. a ready and trained force to dispatch to Africa if crises requiring the U.S. military emerge. The teams will be limited to training and equipping efforts, and will not be permitted to conduct military operations without specific, additional approvals from the secretary of defense.